Pressurized fluid distribution and timing system



July 21, 1964 A. cANDELlsE 3,141,448

PREssuRIzED FLUID DISTRIBUTION AND TIMING SYSTEM original Filed Maron 4,1960 ,I MMM ATTORNEY United States Patent O 3,141,448 PRESSURIZED FLUIDDISTREUTIGN AND TIMING SYSTEM Alfred Candelise, Flint, Mich., assignorto General Motors Corporation, Detroit, Mieli., a corporation ofDelaware Original application Mar. 4, 1960, Ser. No. 12,855, now PatentNo. 3,019,777, dated Feb. 6, 1962. Divided and this application May 24,1961, Ser. No. 112,448 3 Claims. (Cl. 123-26) This is a division of myco-pending application Serial No. 12,855 entitled Air Injection Systemfor an Internal Combustion Engine tiled March 4, 1960, now Patent No.3,019,777.

The invention relates to a system for distributing and timing thedelivery of pressurized fluid to a chamber in timed operation with acycle of operation being carried out within the chamber. As a preferredembodiment, it particularly relates to such a system for injectingcompressed air into the combustion chambers of an internal combustionengine during the engine expansion strokes in order to more completelyburn the fuel contained therein. Use of structure embodying theinvention may also be found in other fluid pressure systems.

It has been found that one of the major sources of atmosphericcontamination is the unburned fuel passing through the combustionchambers of an engine and exhausted therefrom, particularly at idle andlow speed operating conditions. By injecting compressed air during thelatter portion of the combustion step, the otherwise unburnedhydrocarbons will be provided with sufticient oxygen to burn while stillin the engine combustion chambers. This will result in substantiallycomplete elimination of the carbon monoxide content of the eX- haustgases as well as other unburned hydrocarbons. It also increases enginepower and eiciency.

A generally similar system is disclosed in my co-pending applicationSerial No. 12,857, tiled March 4, 1960, now Patent No. 3,073,289, inwhich the air is injected during the latter portion of the engineexpansion strokes through the engine spark plug openings, the air beingtimed and distributed by a valve mechanism operating in timed relationto the engine.

The invention which is the subject of this application providesdifferent means for timing and distributing the air to the enginecombustion chambers.

The invention as embodied in such a system uses an air manifold to whichcompressed air is delivered from a suitable compressed air source andfrom which air is supplied to separate air introducing means for eachcombustion chamber. The air in the manifold provides the air which is tobe injected into the combustion chambers. A separate air circuit isprovided which times the injection of the air from the manifold byactuating a poppet valve which permits air to liow from the manifold tothe various combustion chambers in the proper timed relation.

A rotary air distribution and timing valve assembly of somewhatdifferent construction and operation from that disclosed in myco-pending application, referred to above, is provided. When using thedual fluid pressure system, it has been found that in some instances thepoppet valve will not close immediately when the actuating compressedair is cut off. The modified timing and distribution valve is providedwith a passage which cornmunicates with an engine intake manifold sothat each actuating air conduit is alternately connected to pressurizedair from the compressed air source and to vacuum from the enginemanifold. This construction insures positive opening and closing of thepoppet valve in the timed relation desired.

3,141,448 Patented July 21, 1964 ICC In the drawing:

FIGURE 1 is a schematic presentation of a system embodying the inventionwith a system being installed on a V-type engine;

FIGURE 2 is a partial section view taken in the direction of arrows 2--2of FIGURE 1 with parts broken away and illustrating the details of theair introducing means;

FIGURE 3 is a longitudinal section View ofthe air distribution andtiming valve which is used with the system of FIGURE 1; and

FIGURE 4 is a transverse section view taken in the direction of arrows4-4 of FIGURE 3.

A system embodying the invention is schematically illustrated in FIGUREl. The engine 10 may be of the V-S type and includes banks 12 ofcylinders 14 formed in the engine block 16. Suitable cylinder heads 18may be provided to cooperate with the cylinders 14 and the reciprocatingpistons contained therein to form combustion chambers 20. Spark plugs 22may be provided for each combustion chamber and suitably energized toignite the fuel air charges introduced into the cylinders. Airintroducing mechanisms 24- may also be provided for each combustionchamber and one mechanism may connect with each combustion chamberthrough openings 26 provided for that purpose in cylinder heads 18. Theengine crankshaft 28 may be suitably connected to an air compressor 30to drive the compressor and provide compressed air to the tank 32through conduit 34. Air compressor 30 must provide sufficient airquantities at suiiicient pressures to satisfactorily operate the system.It has been found that the compressor should supply one-half to onecubic foot per minute of air per engine cylinder within a pressure rangeof 30 p.s.i. to 150 p.s.i. while the engine is operating at idle and lowspeed conditions in order to give the best results.

An air distribution and timing valve 36 may be driven by a drivingmember 38 which is in turn suitably connected to a portion of the engine10 which rotates in timed relation to the engine. Drive member 38 isschematically illustrated as being connected to the driving mechanismfor the engine distributor 40 so that the valve 36 will go through thecomplete cycle while the engine 10 operates throughout one completecycle. Thus, in a four stroke-cycle engine the rotatable element ofvalve 36 will make one revolutiorrwhile crankshaft 28 makes tworevolutions.

Conduit 42 receives air from tank 32 and has conduit 44 connectedtherewith and leading to air distribution valve 36 to furnish compressedair to that valve. Conduit 46 is connected with tank outlet conduit 42and conducts compressed air to the air supply manifold 48 which extendslongitudinally along each engine bank 12. Manifold 48 is provided withconduits 50 which connect the manifold with the air introducingmechanism 24 in parallel.

The compressed air discharge ports of air distribution and timing valve36 are connected with a series of conduits 52. Each conduit 52 isconnected to one of the air ntroducing mechanisms 24 to supply timed airfor actuating those mechanisms.

One of the air introducing mechanisms 24 is shown in detail in FIGURE 2.The mechanism includes an adapter 54 which is installed through opening26 and seals against the outer surface of cylinder head 18. A valve body56 is attached to adapter 54 by suitable means such as the threadedsection 58. An air chamber 6 is formed transversely within valve body 56and connects with an air supply passage 62 in which conduit 50 isreceived. Manifold 48 supplies compressed air to air chamber 60 throughconduit 50 and passage 62 and maintains air u) under pressure in thatchamber at all times while the system is operating.

A valve chamber 64 is provided in valve body 60 adjacent threadedsection 58 and a valve seat 66 is formed on the web 68 separating valvechamber 64 and air chamber 60. Valve seat 66 is on the valve chamberside of web 68. A poppet valve '70 extends through valve passage 72formed in web 66 and web 74 which forms a wall for air chamber 60opposite web 68. A valve actuating chamber 76 is formed in valve body 56on the opposite side of web 74 from air chamber 60. Chamber 76 has asuitable valve seal and guide '78 in the end thereof adjacent web 74through which the stem 86 of valve 7@ extends. A valve actuating piston82 is received in the upper end of chamber 76 and is secured to theupper end 84 of valve 70. The side wall 86 of piston 82 is in engagementwith cylinder wall 88. Wall 88 provides a piston guide and seal forpiston 82 in chamber '76. A piston cap 90 is secured and sealed to theupper end of valve body 56 to define a piston actuating chamber 92 andalso to provide suitable connecting means for connecting conduit 52 withthe piston actuating chamber.

A valve closing spring 94 is mounted about Valve stem 80 intermediatevalve seal and guide 78 and piston 82 so as to urge valve '70 into theclosed position. The lower portion of chamber 76 is vented to theatmosphere through port 96.

Valve 70 has its lower end formed to provide valve head 98 which isshaped to seat against valve seat 66. The valve stem portion 160extending through air chamber 60 when the valve is closed is necked downso that the valve stem clears web 68 when the valve is opened and aircan iiow from air chamber 60 through web 68 and past valve seat 66 andValve head 98 into the valve chamber 64 and then through passage 102 inadapter 54 and into combustion chamber 20.

In the operation of the system, compressed air is maintained within themanifold 48 and in each of the air chambers 60 provided in each of theair introducing mechanisms 24. Air is, therefore, maintained at fullpressure up to valve head 98 but is not permitted to pass beyond thatpoint until the valve is opened. An air distribution and timing Valve 36is driven in timed relation with the engine and air under pressure isconducted through conduit 52 to actuating chamber 92 in mechanism 24.The air moved through conduit 52 is so timed that it will act on piston82 to overcome the force of spring 94 and the combustion chamber gaspressures during the engine expansion stroke in the timed relationdescribed in detail in my co-pending application referred to above. Theintroduction of air into the combustion chamber at this time will permitthe otherwise unburned hydrocarbons contained in the combustion gases tomore completely burn, resulting in substantial elimination of carbonmonoxide in the exhaust gases as well as hexane and other unburnedhydrocarbons. This additional burning will increase the expansionpressure in the engine. Engine efciency is increased since the energynormally discarded in the form of unburned hydrocarbons in the exhaustsystem is utilized in the combustion chamber during the power stroke.When the air injection period is completed, air distribution and timingvalve 36 closes the inlet end of conduit 52 and the pressure withinactuating chamber 92 decreases suiciently to permit spring 94 to closevalve 70.

The air distribution and timing valve illustrated in FIGURES 3 and 4overcomes a disadvantage of using the air distribution and timing valvedisclosed and claimed in my co-pending application noted above in a twoair system of the type illustrated in FIGURE 1. If valve 36 closes theinlet end of conduit 52 and tightly Seals that end at the completion ofthe air injection period and no leakby is permitted at piston 82, acolumn of air under pressure will be maintained in conduit 52 andactuating chamber 92 for a time such that valve 78 may not close with ithe exact timing desired. This timing is somewhat critical since acomplete cycle takes place each two seconds when a four stroke-cycleeight cylinder engine is operated at 480 r.p.m., and in one-half secondat 1920 engine r.p.m. To overcome this situation, the distribution andtiming valve 1114 of FIGURES 3 and 4 alternately communicates eachconduit 52 with pressurized air and engine intake manifold vacuum toprovide positive opening and closing of poppet valve 71).

Conduit 44 of the system shown in FIGURE 1 is connected to the end 186of valve housing 108. A rotor 110 is rotatably mounted in housing 108and driven by the driving member 38. Rotor 110 has a longitudinal recess112 extending axially through one end thereof adjacent housing end 186.A rotor extension 114 may be provided on the end of rotor 110 oppositedriving member 38. Extension 114 may extend into a recess formed inhousing end 186 within boss 116 to loca-te the rotor and provide abearing surface. Conduit 44 connects with the boss recess and the rotorlongitudinal recess 112. A radially extending slot 118 is formed inrotor 110 from recess 112 to the rotor outer surface 120. Slot 118 maybe of approximately the same length as recess 112, which extends throughthe rotor to a point adjacent the rotor driving end to which drivingmember 38 is attached.

Valve housing 108 has a plurality of equally spaced radially extendingpassages 122 formed therein, the number of passages being equal to thenumber of air induction mechanisms 24 being used. One conduit 52 isconnected to each passage 122 so that compressed air may be conducted toeach introducing mechanism 24. Passages 122 are illustrated as beinglocated along a pitched line on valve housing 168 in order to facilitatethe installation of fittings or other hardware which connect conduit 52to the valve housing passages. It is for this reason that slot 118 andrecess 112 are preferably formed through a substantial portion of thelength of rotor 110. If desired, however, and space permits, passages122 may be positioned in a circumferential plane. As the rotor rotates,slot 112 will successively communicate with each of the passages 122.These passages are so connected to mechanisms 24 that the mechanisms areactuated in timed relation with the stroke-cycle of each enginecylinder. Compressed air is maintained in recess 112 and slot 118 at alltimes. As the slot 118 connects with one of the passages 122, air underpressure is transmitted to the piston actuated chamber 92 in theassociated introducing mechanism and the valve 70 is opened to admit airto the combustion chamber. The rotor 110 may rotate counterclockwise asindicated by arrow 124 in FIGURE 4. When slot 118 breaks communicationwith passage 122, a compressed air column is maintained in conduit 52and valve 70 continues to be held in the open position by the forceexerted by this column of air. In order to accomplish this, rotor 116must fit closely within housing 108 to minimize air leaks Whilepermitting the rotor to rotate.

A key-way type slot 126 is formed in the outer surface of rotor 110 in alongitudinal direction and parallel to the rotor axis. When the valve isto be used with a four stroke-cycle engine, key-way slot 126 ispositioned circumferentially beyond slot 118 an amount equal to one-halfthe desired crank angle during whichl air is to be injected into thecombustion chamber. Thus, the angle formed at the axis of recess 112between the centers of slots 118 and 126, as viewed in FIGURE 4, wouldbe 50 if the air injection period is to take place through of enginecrank angle.

Valve housing 108 has an annular recess 128 formed around boss 116 andseparated and sealed from the pressurized air inlet 131D which is formedcentrally of the boss. A vacuum conduit 132 is connected with recess 128through housing passage 134 and is connected to a suitable vacuum sourcesuch as the engine intake manifold 136. When the engine and system isoperating, a vacuum is therefore maintained in recess 128 and slot 126.After air from slot 118 has pressurized a valve actua-ting chambar 92and its associated conduit 52 through a passage 122, slot 126 moves intocommunication with that passage 122. The time will be 50 rotor degreeslater, or 100 crank angle degrees later, if that air injection timing isbeing used. When the positive air pressure acting against valve piston82. is relieved, spring 94 immediately acts to close the valve and cutol the supply of compressed air to the combustion chamber 20 from theair supply manifold 28. This system provides positive opening andclosing action of the valve 70 in exact timed relation with the engine.

I claim:

l. A compressed air distribution and timing system for deliveringcompressed air to a combustion chamber of an internal combustion enginein timed operation with a cycle of operation carried out Within saidcombustion chamber, said system comprising air injector means having acompressed air chamber formed therein and valve means for opening andclosing said air chamber to communication with said combustion chamber,valve actuating means including a valve actuating piston chamber formedin said air injector means and valve actuating piston means receivedtherein and secured to said valve, first conduit means including acompressed air manifold connected with said compressed air chamber inthe air injector means for maintaining compressed air in said airchamber, second conduit means for connecting said valve actuating pistonchamber alternately with a source of compressed air and a source ofvacuum in that order so that said valve means is positively opened andclosed in timed fashion by pressure differentials acting on said valvepiston means, and engine driven rotary timing and distribution meansconnected in said second conduit means between said air injector meansand a compressed air source and a vacuum source for controlling theadmission of compressed air and vacuum to said second conduit means intimed relation with the cycle within said combustion chamber.

2, A compressed air distribution and timing system according to claim 1wherein said rotary timing and distribution means comprises, a housing,a rotor rotatably received in the housing, a plurality of openingsspaced circumferentially about the housing and extending therethrough tocommunicate With said rotor having a first passage means formed thereinadapted to be connected with a compressed air source and to successivelycommunicate with each of said openings to deliver compressed air throughthe second conduit means to said valve actuating piston chamber, and asecond passage means formed in the rotor and adapted to be connected toa vacuum source and to successively communicate with each of saidopenings to evacuate the second conduit means, and said valve actuatingpiston chamber, said rst and second passage means being spaced apart atthe surface of the rotor a predetermined angle relative to a cycle ofoperation carried out Within said combustion chamber.

3. A compressed air distribution and timing system for deliveringcompressed air to the combustion chambers of an internal combustionengine in timed operation with a cycle of operation carried out Withinthe combustion chambers and comprising, an air compressor driven by theengine to provide a source of air pressure for the system, a rotarydistribution valve driven in timed relationship by the engine, airinjector means opening into the interior of each combustion chamber andincluding air operated Valve means for controlling the opening andclosing of the air injector means, pressure conduit means connected tothe air compressor and including a first branch circuit having an airmanifold connected in parallel with each air injector means and a secondbranch circuit connected with the rotary distribution valve, vacuumconduit means adapted to communicate with a vacuum source and connectedwith the rotary distribution valve, and air operated valve conduit meansconnected between the rotary distribution valve and each air injectormeans for alternately delivering pressure and vacuum to operate said airoperated valve means, said rotary distribution valve being operable toalternately connect said air compressor and vacuum source sequentiallyto said air operated valve conduit means to operate said air operatedvalve means in timed order according to the timing of the engine.

References Cited in the file of this patent UNITED STATES PATENTS885,459 Engler Apr. 21, 1908 2,383,349 Slick Aug. 21, 1945 2,447,423Nies Aug. 17, 1948 2,598,754 Booth June 3, 1952 2,616,997 Favre Nov. 4,1952 2,818,881 Bonner Ian. 7, 1958

1. A COMPRESSED AIR DISTRIBUTION AND TIMING SYSTEM FOR DELIVERINGCOMPRESSED AIR TO A COMBUSTION CHAMBER OF AN INTERNAL COMBUSTION ENGINEIN TIMED OPERATION WITH A CYCLE OF OPERATION CARRIED OUT WITHIN SAIDCOMBUSTION CHAMBER, SAID SYSTEM COMPRISING AIR INJECTOR MEANS HAVING ACOMPRESSED AIR CHAMBER FORMED THEREIN AND VALVE MEANS FOR OPENING ANDCLOSING SAID AIR CHAMBER TO COMMUNICATION WITH SAID COMBUSTION CHAMBER,VALVE ACTUATING MEANS INCLUDING A VALVE ACTUATING PISTON CHAMBER FORMEDIN SAID AIR INJECTOR MEANS AND VALVE ACTUATING PISTON MEANS RECEIVEDTHEREIN AND SECURED TO SAID VALVE, FIRST CONDUIT MEANS INCLUDING ACOMPRESSED AIR MANIFOLD CONNECTED WITH SAID COMPRESSED AIR CHAMBER INTHE AIR INJECTOR MEANS FOR MAINTAINING COMPRESSED AIR IN SAID AIRCHAMBER, SECOND CONDUIT MEANS FOR CONNECTING SAID VALVE ACTUATING PISTONCHAMBER ALTERNATELY WITH A SOURCE OF COMPRESSED AIR AND A SOURCE OFVACUUM IN THAT ORDER SO THAT SAID VALVE MEANS IS POSITIVELY OPENED ANDCLOSED IN TIMED FASHION BY PRESSURE DIFFERENTIALS ACTING ON SAID VALVEPISTON MEANS, AND ENGINE DRIVEN ROTARY TIMING AND DISTRIBUTION MEANSCONNECTED IN SAID SECOND CONDUIT MEANS BETWEEN SAID AIR INJECTOR MEANSAND A COMPRESSED AIR SOURCE AND A VACUUM SOURCE FOR CONTROLLING THEADMISSION OF COMPRESSED AIR AND VACUUM TO SAID SECOND CONDUIT MEANS INTIMED RELATION WITH THE CYCLE WITHIN SAID COMBUSTION CHAMBER.